The pathology and gene expression core will provide services to the program project members using histology, immunohistochemistry, and mRNA in situ hybridization involving their various experimental models relating to the immunologic basis of asthmatic lung disease. This core will provide technical support for routine morphology and protein and gene expression studies as well as microscopic and pathologic evaluation. The principal advantage of this core is the centralization of expertise, quality control and cost saving afforded by economy of scale, maintenance of large equipment and automation of techniques in a central laboratory. This support will be provided to all of the core projects in the program through the expansion and utilization of an established centralized core lab based in the Department of Pathology which provides technical and analytical expertise to support and enhance a wide range or morphologic based studies particularly through the use of mouse animal models or experimental systems. The rationale for this proposal is based on a combination of factors which together will provide the basis for a comprehensive core program which will build upon the existing expertise and experience of the PI in utilizing morphology based experimental animal systems to study the immunologic basis of the role of biologically active cytokines in the pathogenesis of asthmatic lung disease in an experimental mouse animal system. The core will provide: 1) Technical support for routine morphology based techniques including in situ hybridization, immunohistochemistry, tissue processing, and routine special histochemical staining. 2) The core will provide experienced microscopic analyses, extensive pathologic interpretation and consultation to the investigators regarding the interpretation of the morphology data as well as additional professional guidance and experimental design. The core will also maintain a web based database including microscopic interpretation, descriptions, and representative illustrations. 3) The core will also support the development of new technology to enhance the program project investigators morphologic techniques as well as becoming an educational resource for the program. Altogether, the core will provide accurate, efficient and cost effective morphologic based gene expression analyses with significant savings compared to having each individual investigator performing an establishing this laboratory support for their project.